280AI hand loads

[rharfo]

Preparing for a upcoming hunt. Shooting out to 400 yards and my dope is off- shooting several inches high. I chrono rounds that I've been shooting and they are 100 feet per second faster then the loads I set zero with. So three batches of brass two are fire formed Rem, third is fire formed Nosler. One batch of Rem is 100 fps faster. Why? If all things equal how? Using IMR 4831 60.0 grains. 140 Accubond Fed 210 primer.
Soooo if I shoot up my original zeroed loads will the next batch shoot same speed? I leave in 4 weeks!
Never had such a big change in speed like this before....

 

[Jokostel]

Different brass thicknesses... possibly different lots of powder/primers/bullets.
Or a slight possibility of you flubbing the charge a bit.
Use the one batch with the hunt.... or get ALL of the same lot ## of materials, and load a batch.

 

[Rifleman513]

Not sure if this is your issue, but I shoot a 300 RUM and have noticed quite a few posts about people starting with rem brass then buying the nosler brass when it came out and it has less capacity.

It could be possible that your rem brass may be from separate batches and has a fair amount on variance.

Try eliminating one variable at a time and see what it does. I would load a couple of the suspect rem cases and pay close attention to each process (especially charge weight) and shoot a few over the chrono.

I will admit that I have got about halfway through a batch of 20 rounds before I realized I didn't pay attention to my scale and was a grain +/- than what I thought.

 

[RevJim]

Go back to the Remington brass...load 61gr R22 and the Nosler 150BT with a CCI BR2 primer. Zero +3 at 100 and shoot out to 350 w/confidence. Actually, the Remington will show higher pressure with your existing load simply because it is "thicker" than Nosler ( actually Norma) brass. No mix n match brass with a wildcat! Have a great hunt bro!

 

[rharfo]

Thanks everybody. For what it's worth I watch each load and won't use it if it's not exactly 60.0. I throw the powder back if it's 60.1! I'm using a RCBS digital powder dispenser scale combo. Like most of you said it's gotta be a brass issue. My Rem brass is mixed with newer and older. Lesson learned. Gonna shoot more this week. Fingers crossed.